STEP (satellite)
Encyclopedia
The Satellite Test of the Equivalence Principle (STEP) is a proposed space science experiment to test the equivalence principle
of general relativity
. The experiment is thought to be sensitive enough to test Einstein's theory of gravity and other theories.
The basic configuration is that of a drag-free satellite where an outer shell around an inner test mass is used to block solar wind
, atmospheric drag, the Earth's magnetic field
and other effects which might disturb the motion of a freely-falling inner object.
Equivalence principle
In the physics of general relativity, the equivalence principle is any of several related concepts dealing with the equivalence of gravitational and inertial mass, and to Albert Einstein's assertion that the gravitational "force" as experienced locally while standing on a massive body is actually...
of general relativity
General relativity
General relativity or the general theory of relativity is the geometric theory of gravitation published by Albert Einstein in 1916. It is the current description of gravitation in modern physics...
. The experiment is thought to be sensitive enough to test Einstein's theory of gravity and other theories.
The basic configuration is that of a drag-free satellite where an outer shell around an inner test mass is used to block solar wind
Solar wind
The solar wind is a stream of charged particles ejected from the upper atmosphere of the Sun. It mostly consists of electrons and protons with energies usually between 1.5 and 10 keV. The stream of particles varies in temperature and speed over time...
, atmospheric drag, the Earth's magnetic field
Magnetic field
A magnetic field is a mathematical description of the magnetic influence of electric currents and magnetic materials. The magnetic field at any given point is specified by both a direction and a magnitude ; as such it is a vector field.Technically, a magnetic field is a pseudo vector;...
and other effects which might disturb the motion of a freely-falling inner object.